


Insomnia

by themidnightpost



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Alternate Universe - Victorian, Blood, Horror, M/M, Psychological Horror, hopefully you will tho, poor linhardt's just not gonna have a good time
Language: English
Status: Completed
Published: 2020-12-28
Updated: 2020-12-28
Packaged: 2021-03-11 02:40:56
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,450
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28387932
Author URL: https://archiveofourown.org/users/themidnightpost/pseuds/themidnightpost
Summary: Working late into the night, Linhardt accidentally spills a sample of a peculiar blood type that he and Professor Hanneman are jointly conducting research into. Even after cleaning up and carrying on, Linhardt now feels strongly as though he is being watched, and each night that feeling grows stronger, until he can no longer sleep.
Relationships: Linhardt von Hevring/My Unit | Byleth
Comments: 4
Kudos: 17





	Insomnia

Professor Hanneman prepares himself to leave the laboratory after yet another long day of work, sighing a small amount as he notes the time on his pocket watch. Before he departs, however, he turns back from the door towards the occupant of the desk set against the far wall.

“That will be all from me today. I highly advise that you rest soon as well, Linhardt. You do have a tendency to work doggedly through the night, only to exhaustedly stumble home in the morning, if you even leave at all.”

Linhardt barely acknowledges him with a slight hum, quill skating across his paper while his left hand traces text from the massive volume open next to him.

Hanneman sighs again and shakes his head, “Very well, I’ll see you in the morning.”

Answered with another distracted hum, Hanneman closes the laboratory door behind him, only the scratching sound of Linhardt’s quill left in the still and quiet room. Lit only with a lantern on his desk, Linhardt barely seems to take notice of his surroundings beyond the notes and book in front of him. 

Once the researcher finally gets up from the desk, he stretches his arms and walks over to a wooden counter built against the far stone wall. Several neatly labeled vials of blood are lined up on it, and he searches for one in particular with his stomach turning only slightly. Back when Linhardt first began his biological studies, he dreaded anything to do with blood, even passing out cold onto the floor the first time his professor brought out a sample to demonstrate for the class. Now, however, he can outwardly control his immediate reactions to an almost frightening degree, although he never inwardly lost his disgust for the substance. 

Linhardt brings a labeled vial to another counter, ferrying the focal point of his studies with the immense care it deserves. After preparing the next vital instrument, he uncorks the sample and uses an eyedropper to pull out only what he needs. Despite how careful he is, however, when Linhardt attempts to reseal the container, the cork goes in at an incorrect angle. Within the blink of an eye, the vial tilts and most of its blood spills across his left hand.

He scoffs at himself in frustration, immediately sealing the vial correctly to save what he can of the sample, and hurries to the washbasin in a corner.

_Eugh, that was careless of me. That blood type is exceedingly rare too._

Linhardt takes care to ensure that he cleans his hand well, then turns back to continue his work. A few seconds later, however, he stops.

The hairs on the back of his neck prick up.

Lindhart’s eyes quickly dart around the room, and he remains frozen for a few moments. 

_...there is no one else in here. It’s irrational to feel like someone would be watching me._

He returns to his work, but the sense that he is not alone does not fade.

The clock only strikes 3AM when Linhardt stops for the night, and before he can question his decision to leave prematurely, finds himself already walking home.

_I just need some more sleep…_

Leaving the lab does not assuage the nagging feeling that someone is watching him, however. In fact, it grows ever stronger, as though he were being followed.

So for the first time in his life, Linhardt’s gait grows lively, and during the course of his kilometer-long walk home, never once looks back.

He is not surprised to find the lights off when he returns home. What does surprise the researcher, however, is his need to light a candle before venturing up the stairs. Linhardt is not the sort of man who dreads invisible dangers in the dark, or fears what it could possibly now be obscuring within his home. 

But tonight? Tonight does seem to be another matter entirely.

Just as he enters the bedroom and softly closes the door behind him, a rustle of fabric from beyond the candle’s sphere of illumination draws his attention.

“Lin…? What are you doing back home so early?”

The smallest of smiles peeks out of his expression as Linhardt sets the candlestick down on the bedside table and sheds his coat and shoes. “I wanted to take a nap. Make some room, will you?”

Byleth rolls away from the centre of their large bed and watches as his husband climbs in after him still fully-clothed, not even bothering to unbutton his waistcoat. This in itself is not a rarity, however... 

“Why didn’t you leave your coat downstairs?”

Linhardt blows out the candle and burrows underneath the covers. He was not about to verbally bring his worries to life, not when he was so close to the rest he craved, “I’m sleepy... Good night, By.”

“...Good night.”

 _How cruel,_ Linhardt thought as he watched Byleth fall back asleep so quickly and easily, _that is usually my forte._

See, that is the thing with nightmares. They terrify you, and have you fight to wake up in order to escape them. An indisputable connoisseur of sleep, Linhardt has undergone his fair share of nightmares, and each time came out the other side perfectly unrattled.

He’s seen them all: failing out of his research programme, monsters forcing him to exercise by chasing him endlessly, and even some horrifically realistic dreams featuring him and his loved ones fighting in an ongoing, brutal war.

But this? This was different.

At first, Linhardt could barely even tell that he was dreaming. That is the point of dreams though, is it not? For Linhardt, however, he very often could swiftly tell his dreams apart from his waking life, given the sheer amount of experience he has from consistently roaming his own unconsciousness.

What set this one apart from the others though, is how relatively unremarkable it is.

At least, at first.

He is at home, sitting by the fireplace, and engrossed in a book. It could have been any day at all in his life. But he can not read the book at all. Not just because the book in his hands is doubtlessly some jumble of random symbols his mind conjured for the purposes of staging tonight’s little jaunt, but because the looming figure next to him won’t allow Linhardt to focus on anything else.

He shuts the book and gets up from the armchair to slide it back onto the bookshelf, willfully keeping his eyes facing forward and forbidding them from straying towards their peripheries. Linhardt can feel the figure draw closer still, visually dissecting his every move, every twitch of his fingers, every flutter of his pulse under his skin. 

It does not matter where he moves to, what he does, or how hard he disciplines himself into ignoring the figure—it only keeps growing closer, yet impossibly never touching him. When it finally speaks to him though, Linhardt freezes in that dreamlike way that overrides every cell in his body screaming at him to move, move far away.

It has Byleth’s voice.

Against his will, Linhardt finds himself turning back to look at the figure.

“Lin!”

His eyes fly open, Byleth’s concerned expression swimming into view above him.

“I am so sorry to awaken you. Are...are you feeling better now?”

Linhardt’s slow blinking contrasts against his fast breathing, and it takes a few moments for his brain to make the rest of the jump into the waking world with him.

“...yes, I’m fine. Why would you ask that?”

Byleth frowns slightly, which is saying something as he almost always appeared to be doing so anyhow, “You were tossing and turning so much that I thought the bed might break. I don’t remember you ever reacting to a nightmare like that before.”

Linhardt blinks deliberately, almost expecting to see the figure’s face waiting for him on the inside of his eyelids, “It was unlike any I’ve had before, yes.”

He then looks at Byleth more closely, noting that he was standing at Linhardt’s bedside and fully dressed, “I take it it’s morning now?”

Byleth nods, “I need to leave soon if I’m to make it to the university on time to give my morning lectures.” He looks briefly towards the opaque curtains still drawn over the bedroom window before turning back to Linhardt, “Would you like for me to leave those be so that you can go back to sleep?”

In yet another first for him, Linhardt shakes his head and moves to get out of bed, “No thanks. I have a lot of work to do.”

“But you’ve only slept for four hours,” Byleth answers with a deadpan stare.

“Doesn’t matter, I can more than make up for that later.”

“...alright then. Do take good care of yourself though, and I’ll see you when you get back home.”

Linhardt nods, sharing a quick peck with Byleth before the professor hurries out of the room and down the stairs.

_Don’t get me wrong, I would love nothing more than to go back to sleep._

But he can not risk running into that face again so soon.

It didn’t matter where Linhardt went. The sense that he was being watched only ever grew stronger.

He did not stay at home for very long, opting to eat the sandwich Byleth made for his breakfast while on his walk back to the laboratory.

It’s funny how feeling eyes on you can severely diminish your appetite.

When Linhardt enters the lab, he feels one more gaze land on him.

“Ah, Linhardt. What brings you back in so early?”

“I wasn’t able to finish all of my work last night.” Linhardt makes a beeline for his desk, as is routine. What is not routine, however, is the way Hanneman can see Linhardt’s jaw and shoulders clenched as solid as metal.

“Forgive my asking Linhardt, but are you well?”

“I will be quite fine, Professor Hanneman. Especially after we complete this study.”

Hanneman’s eyebrow rises but a smidge, but he does not press the matter, and the two quietly resume their research.

* * *

The following two weeks unravel in much the same way that Linhardt’s sense of peace does.

While he could at first maintain it by pouring his focus into literally anything else, he quickly lost any solace that could have offered him. Because it never mattered what he did, Linhardt was always being watched.

And what made the whole affair worse was that there did not seem to be any way to determine _how_ that was even occurring.

There _were_ visible changes he could note, however.

It started with a book standing on a different shelf here, a graph with altered data there, and did not end with clothes in his wardrobe going missing or previously unused fireplaces crackling to life. Every change, no matter how small, rings an increasingly louder alarm bell in Linhardt’s head. 

And within a fortnight, Linhardt recognises each as burgeoning proof that someone—or something—is targeting him.

Over time, the expressions that both Byleth and Hanneman’s faces form in response to Linhardt’s speech and actions, warn the young man that they are growing increasingly wary of him. However, as neither of them think to communicate with the other, nothing changes. And as their concerned confusion grows all the more apparent, Linhardt’s descent is so fueled further.

* * *

Another four nights pass. However, these in particular do so while withholding the one thing Linhardt seeks above all else: sleep.

As Byleth slumbers on beside him and Hanneman works in tandem with the researcher, Linhardt privately bemoans his insomnia. He does not say a word on the matter, however. While it is not exactly against his nature to bellyache, the other mens’ behaviour have only been setting him even further on edge. And the last thing he needs is ever more sets of eyes permanently locking onto him.

In spite of everything though, there is a light at the end of the tunnel.

If his hunch is correct (and they usually are), Linhardt’s research is precariously close to a breakthrough. Just one more day of work should do it, he is so close to finally unlocking the secrets of the rare blood type that he spilled onto himself weeks earlier.

And when he does, this nightmare will finally come to an end.

Eagerly, Linhardt makes his way back to the lab with a greater spring in his step, despite his notable lack of sleep. He all but bursts into the lab, momentarily startling Hanneman. With his coat still on and seemingly all peripheral vision lost, Linhardt surges towards the counter where the blood samples are stored. He searches, eyes scanning over their labels in an increasingly frantic manner as his much fuzzier hearing barely registers the questions addressed to him.

Once, twice, thrice...over ten times, Linhardt pulls out vial after vial, hunting for the one he spilled. He knows that it should be fairly easy to find, due to it now being a quarter of the way filled, at best.

But it is not there.

With the last vial he checked still in hand, Linhardt turns towards the shelf set aside for his files. He ransacks through the books and documents stored there, eyes very much attuned to those he marked off as referencing that blood type.

They too are nowhere to be found.

Only then does Linhardt turn around, vaguely surprised to find Hanneman right behind him, arm extended towards his shoulder as if just seconds from reaching the younger researcher.

“Linhardt…”

“Professor Hanneman, where’s my documentation on type S!?”

“...why—?”

“And the samples! There’s a vial that’s almost empty from when I spilled it!”

“You spilled a sample? When did—wait, it matters not—what exactly are you referring to?”

Some remote corner of his mind registers amazement while Linhardt feels his hands creeping up towards his hair, as if ready to pull it.

 _This must be why other people engage in such a pointless motion_ , he infers for only a moment before descending back into his building panic.

“Blood type S! The focal point of my research all this past year! Where is it!?”

Linhardt internally flounders further as he watches Hanneman take a step back from him, and then another.

_Why am I acting this way? This isn’t like me. This isn’t like how anything was before—_

“Linhardt. Please listen to me very carefully. The blood type S...it is only an urban legend. A little academic ‘what-if’. It doesn’t truly exist.”

All of Linhardt’s thoughts crash to a halt, and then they spin all the wilder.

“That’s ridiculous. I’ve been researching it since I joined your laboratory, it is the reason I am even here to begin with. If...if it actually does not exist, then what have I been working on all this time!?”

Hanneman sighs, and his face falls into an expression that Linhardt can’t quite interpret, “I have been wondering why you were so doggedly focused now on water, of all things.”

Linhardt looks back down to the vial in his hand. The liquid inside is clear.

Hanneman pats him sympathetically on the shoulder, “So much uninterrupted work would take a toll on anyone. I recommend that you take some time off, to rest and recuperate.” 

Linhardt knows it is not a recommendation, but a mandate. 

He does not process anything else, singularly focused on the vial in his hand.

Byleth attempts to console Linhardt as he paces in front of their fireplace, but his words barely register as the latter continues muttering to himself.

“This can’t be the case. My research would have been halted if I was really turning in rubbish about water. There must be something else.”

“Lin, I really think you should sit down and rest.”

“But what’s missing? I was so close to a breakthrough. Just one more day and I’d have uncovered type S’s secrets.”

Byleth freezes as if his own blood had just run cold, “...could you repeat that?”

“...Blood type S.” Linhardt responds, some semblance of sanity reigniting in his eyes as he finally grants Byleth his undivided attention, “What do you know?”

The professor opens his mouth to speak, but stops, shakes his head, and continues with a different thread, “Have you ever come into any bodily contact with it?”

“It did at one point spill across my left hand. But I washed it off quickly enough.”

“On what day did that occur?”

“A little over a fortnight ago. Why does that matter?”

Byleth’s frown grows deeper, “Don’t you remember? Two weeks ago, you accidentally cut your left hand when slicing fruit for breakfast. It might not have had time to heal before you left for work that day.”

Realisation dawning upon him, Linhardt hurries to the kitchen to look for the fruit knife, as if expecting to find it pronounced guilty with his own blood still staining the blade, even all these weeks later.

However, his decidedly pale face loses even more colour when he sees Byleth already in the kitchen, preparing Angelica Tea for his husband.

“Lin? What is the matter?”

Linhardt stares for several long moments at the tea, his favourite blend, a reliable comfort through times both good and bad.

_...He’s poisoned it._

“How are you here? What are you doing?”

Byleth raises an eyebrow, “Making tea. I thought it would help you feel better.”

Linhardt shakes his head and slowly backs away, mind fighting an uphill battle against its own sluggishly declining pace, “But you were in the library just now... Prove to me that you’re real.”

The latter frowns in concern, “Why don’t you get into bed, I’ll be right up with some calming tea for you.”

“I can’t! I haven’t slept in four days! Don’t you understand? I won’t be able to sleep until I’ve uncovered this blood’s secrets!”

“But you already have.”

Linhardt shakes his head in disbelief, finding that he is struggling to blink, “No, I haven’t. Not yet. What gave you that idea?”

“Hanneman contacted me before you arrived home today to share the good news. Sorry that he spoiled the surprise, I am still very proud of you.”

Unable to hold back a bark of sardonic laughter, Linhardt pushes down the way his heart swells at Byleth’s words, “Professor Hanneman contended that the blood type was imaginary. One of you is lying!”

He then makes for the front door, flings it open, and races out of the house in the direction of the laboratory.

_I am not mad. I am not mad!_

All the while, the feeling that something was following after him grew all the stronger.

Linhardt did not bother to look back, however. The only way left to him was forward.

Before he rounds the last corner towards the lab, Linhardt already knows it is too late.

Flames dance against the night sky, and as he draws closer he can not deny that it is in fact their laboratory that is burning down.

_The books. The blood. Our work. Everything. It’s all...burning._

He can not get any closer, however, as the fire department had cordoned off the area and are already at work dousing the flames. That of course does not stop him from trying.

Linhardt steps off to the side, dips underneath the rudimentary barrier that was hastily set up, and makes a run for it.

“Hey, you! Get away from there!”

A fireman breaks rank just long enough to grab onto Linhardt’s shoulders, pushing him back towards the swelling crowd of spectators, “Are you daft!? You’ll die in there! Stay back!”

Linhardt stumbles, both in body and in mind, against the congregation. He does not realise that he’s fallen to his knees until he feels strong arms encircling him. He then blinks up blearily to see Byleth’s face blocking out the scorched sky. 

“Byleth…”

“I’m here, Lin.”

“Are...are you real?”

Brow furrowed, Byleth closes the gap between them with a gentle kiss, “I promise you, Linhardt. I am real.”

He scoops up the researcher as easily as if he was a rag doll, and gazes into Linhardt’s eyes with a desperation that he’s never once seen before, not in all of their years together.

“Please, Lin. Come home. Just come home with me and get some sleep.  
“Let yourself, and this whole thing, rest.”

“...okay. Let’s go home.”

Before they leave, Linhardt looks back towards the now substantial mass of people gathered on the street, watching the laboratory fall to ashes. And one person turns back to him. 

It is Professor Hanneman, who holds his gaze for what feels like an eternity, before shaking his head.

Linhardt blinks, and Hanneman is gone.

**Author's Note:**

> And then Linhardt went on back home and had the best dang sleep he'd ever slept.  
> Fin  
> As for everything else? Oh, who knows? <3
> 
> In the meantime, [come bug me on twitter](https://twitter.com/MemeLordPost) about Byhardt, or pretty much any Three Houses ship you wanna chat about!


End file.
